Charge and spin order in molecular conductor exhibiting giant magnetoresistance

在酞菁分子导体中，观察到巨磁电阻效应。为了阐明这种磁电阻的机理，我们在强磁场下进行了高精度的X射线衍射测量。我们发现，在外加磁场作用下，波数为4k_F的弥散条纹的强度降低。如果这种扩散条纹归因于电荷有序，则巨磁电阻是由磁场诱导的电荷有序抑制引起的。

In the phthalocyanine molecular conductor, the giant magnetoresistance is observed. In order to clarify the mechanism of this magnetoresistance, we performed the high precision X-ray diffraction measurement under the high magnetic field. We found that the strength of the diffuse streak having the wave number of 4k_F decreases under the applied magnetic field. If this diffuse streak is ascribed to the charge order, the giant magnetoresistance is caused by the magnetic-field-induced suppression of the charge order.